1. Field of the Invention
The present invention relates to a mobile communication terminal including multiple identity cards.
2. Discussion of the Related Art
A mobile communication service provider or a mobile carrier generally authenticates the use of a service based on subscriber identification information transmitted from each mobile communication terminal and charges the user for using the service. The mobile communication service provider also stores information needed to use the service, such as a telephone number of a subscriber, a subscriber authentication key, an encryption module, and service network information in a card medium, and mounts the card medium in the mobile communication terminal to thereby provide a communication service to the mobile terminal.
In more detail, the card medium is referred to as subscriber identity module (SIM) card in the Global System for Mobile Communications (GSM) system, a Universal Subscriber Identity Module (USIM) card in the Universal Mobile Telecommunication System (UMTS), and a User Identity Module (UIM) card or Removal User Identity Module (RUIM) card in the Code Division Multiple Access (CDMA) system. Further, when a mobile terminal having a SIM card is turned on, the terminal first transmits user identification information stored in the SIM card to a service provider through a service network and receives an authentication for using service from the service provider.
In addition, some terminals include multiple SIM cards. In this instance, the user manually activates one of the cards corresponding to a desired service. For example, when a terminal has two slots with two SIM cards mounted therein (i.e., SIM cards A and B), the user selects one of the A and B SIM cards, and uses a service corresponding to a telephone number of the selected SIM card.
That is, when the user selects the A SIM card, the mobile terminal is recognized by the telephone number of the A SIM card and thus receives calls and messages directed at the telephone number of the A SIM card. Further, in this instance, the B SIM card remains inactivated and a service corresponding to the telephone number of the B SIM card is not available. A similar concept applies to when the user selects the B SIM card. Thus, the user is unable to receive calls or messages on a deactivated SIM card.